1. Field of the Invention
The present invention relates to fixing apparatus that fixes a developer image onto a sheet by heating, and particularly to a temperature control technique to control heat applied to a sheet.
2. Description of the Related Art
Traditionally, a technique of increasing heat capacity of a roller and power of a heat source has been known in order to avoid troubles caused by temperature fall in the roller in the case of performing fixing processing to a large number of sheets at a high speed in a fixing apparatus that fixes a developer image onto a sheet by heating (see, for example, JP-A-8-211769).
However, with the traditional technique, in an image processing apparatus having a scanner, power required for turning on a scanner lamp is distributed to an auxiliary heater of the fixing apparatus when the scanner is stopped. Therefore, there is a problem fixing processing to a large number of sheets cannot be carried out at a high speed while the scanner is being operated.